Writing instrument, particularly of the ball point type



H. BROSS June 1961 WRITING INSTRUMENT, PARTICULARLY OF THE BALL POINTTYPE Filed March 8, 1956 United StatesPatent O 2,989,032 WRITINGINSTRUMENT, PARTICULARLY OF THE BALL POINT TYPE Helmut Bross,Braunschweig, Germany, assign'or, by mesne assignments, to Frank T.Johmann, Berkeley Heights, NJ.

Filed Mar. 8, 1956, Ser. No. 570,330 Claims priority, applicationGermany Mar. 25, 1955 12 "Claims. (Cl. 12042.03)

The present invention relates to a writing instrument having a slidablewriting means carrier, particularly a ball point type refill, which isunder the influence of a spring force resisting the writing pressure,which writing instrument," by urging the entire stem or casing thereofagainst a suitable support, may be brought into an operative position inwhich the writing point of said carrier or refill is advanced for use,and which writing instrument may be brought back into an inoperativeposition by again using the entire stem thereof to urge the said writingpoint against the said support. The operation of the mechanism of knownwriting instruments of this type is a function of pressure, and properoperation requires a certain amount of skill on the part of the user,rendering malfunctioning unavoidable.

It is one object of the present invention to provide improvements in awriting instrument of the type indicated as regards both itsconstruction and its operation. An essential feature of the writinginstrument of the present invention resides in the provision of apositively operating indexing or shifting and locking mechanismcomprising suitable means, such as rigid stops, which serve to limit theoperative stroke length required for withdrawing and advancing,respectively, the said Writing means carrier. Since the length of thesaid operative stroke substantially corresponds to the largest possibledistance traveled by the respective part or parts, the operation of thewriting instrument is extremely simple and requires no particular skillon the part of the user.

According to still another feature of the invention, even the movementof the writing means may be limited by a fixed stop.

Furthermore, the invention is concerned with other details of the designof the casing or stem as well as the locking mechanism. 7

Other objects, features and advantages of the presen invention will bereadily apparent from the following detailed description of a preferredembodiment thereof taken in conjunction with the accompanying drawings,in which:

FIG. 1 is a longitudinal sectional view, partly in elevation, of theball point pen of the invention, of which the pressure-exerting tubularmember has fixedly attached thereto a toothed sleeve member;

FIG. 2 is a development of the advancing and withdrawing mechanism usedin the embodiment of FIG. 1;

FIG. 3 is a longitudinal view, partly in section, of a modifiedembodiment in which a pressure-exerting tubu-. lar member carries asleeve member provided with teeth on one end only and both slidable androtatable relative to said tubular member; and

FIG. 4 is a schematic representation, partly developed into the drawingplane, of the withdrawing and locking mechanism provided in theembodiment of FIG. 3.

Referring now more in particular to the drawings, in FIG. 1 thereference numeral 1 indicates the front portion and 2 the rear portionof a rigid two-piece stem or sleeve of a ball point writing utensil. Astyle actuating or pressure-exerting member 4 of tubular shape carriesbetween its ends a fixed shifting sleeve 3 and, near one of its ends, aclamping means 5 which serves to grip an Patented June 20, 1961 elongatecylindrical writing style or ball point pen refill 6 inserted into thepressure-exerting tubular member.

. Provided on the inside of the rigid stem or casing 1, 2

are two rail-like projections or pawls 7 and 8, each of which cooperateswith one of the toothed end faces of the ratchet element or shiftingsleeve 3. On its rear end the said shifting sleeve carries a pluralityof ratchet teeth or sawteeth 9 of uniform depth, and provided on thefront end face of said sleeve are projections, the number of which ishalf that of the said sawteeth, the end faces of the said projectionseach carrying two sawteeth 10. The pressure-exerting tubular member 4 issubjected to the action of a compression spring 11 adapted to withstandthe writing pressure. The front portion of the stem or casing 1, 2carries a compressible member 1' the external contour of which mergesinto the curved or cambered contour of the entire writing utensil;disposed interiorly of said compressible member 1 is a centrallyapertured point or slidable supporting tube 12 which, while preventingthe compressible member from being distorted by bending, forms a hardpoint 12'.

With the ball point refill '6 in the writing position shown in FIG. 1,the actuator or pressure-exerting tubular member 4, which is acted uponby the spring 11, rests with a longer interspace 13 (FIG. 2) between thepojections 10 against the fixed shifting rail 7. Upon the writing pointof the writing utensil being urged against a support, the ball penrefill, together with the pressure-exerting tubular member and itsshifting sleeve, is urged inwardly until one of the teeth 9 strikes theupper shifting rail 8. The inclination 14 of the rail 8 cooperating withthe slanting faces of the teeth 9 produces a rotation of the shiftingsleeve 3, together with the tubular member 4, this rotation, accordingto the depth of the teeth, amounting to one-half tooth spacing andoccurring in the direction of the arrow 15 in FIG. 2. When the tubularmember, upon the operating pressure being removed, is again advanced bythe spring 11, the shifting rail 7, while producing a further rotationby onehalf tooth space, engages in the space 16 between the two sawteeth10. This locked position corresponds to the withdrawn position of thetubular member and the ball pen refill. Upon a further operation byurging the writing point against a support, causing also the pointmembers 1, 12 and 12 to be urged inwardly by a small amount, theshifting operations will occur in a similar manner, causing the space 13of the shifting sleeve 3 again to assume a position above the shiftingrail 7. This position corresponds to the writing position in which thevarious parts are again in the position indicated in FIGS. 1 and 2. Alsoduring this operation, the shifting rail 8 constitutes the fixed stoplimiting the motion of the ball pen refill.

Shown in FIGS. 3 and 4 is a ball point pen incorporating a modified formof back pressure and locking mechanism in which the tubular member willnot be rotated and which aifords greater dependability in operation.Slidably and rotatably supported on the tubular member 34 is a shiftingsleeve 18 which is provided with teeth on its rear end face, and whichis urged rearwardly by a compression spring 17 disposed between the saidshifting sleeve and a collar formed on the tubular member. Associatedwith the flat front end face 19 of the shifting sleeve is a stop 20carried by the inner wall of the casing of the writing utensil. Thetoothed rear end face of the shifting sleeve cooperates with a shiftingrail 21 projecting from the tubular member and with another shiftingrail 22 provided on the inside of the said casing 32. The tubular member34 is slidably mounted but is held against rotation, and it is actedupon by a compression spring 23 the force of which is greater than thatof the spring 17. The movable shifting sleeve has formed on its rear enda plurality of projections 24, the end faces of each projection carryingtwo rearwardly oriented sawteeth 25. The beveled rails 21 and 22 arearranged in close proximity to one another.

In the illustrated position of the various parts, the tubular member 34is in a position in which the ball point refill 6 is in its advancedwriting position. When the tubular member 34 is moved in the directionof arrow 26 in FIG. 4 by urging the ball pen refill located therein inthe same direction, the shifting sleeve 18 is retained by the rail 22provided on the inside of the casing member 32, whereas the tubularmember 34 carrying the rail 21 continues to move inwardly. Upon the rail21 emerging from the long slot 27 of the shifting sleeve, the latter isreleased in the direction of rotation and is rotated by onehalf shiftingspace by the beveled surfaces 28, causing the rail 21 of the tubularmember 4 to move into the space 29 between the two sawteeth 25, the rail21, by way of the shifting sleeve 18, resting against the stop 20 in aposition which corresponds to the withdrawn position of the ball penrefill. Upon the mechanism being operated again, the various partsthereof will again assume their original positions shown in FIG. 3. Thewithdrawing and operating mechanism just described also constitutes asingle-step mechanism in which the operating stroke may always be of thesame magnitude, being selectively limited by a fixed limiting stop. Thesaid limiting stop may, for example, be provided in the form of apinshaped extension 30 of the tubular member, which extension, when inits operative position, engages the inner end face of the rear end ofthe casing member 32. It will be appreciated that the length of strokemay also be limited by the extent to which the compressible member 1 ofthe front section 1 of the casing can be compressed, in which case thesaid pin-shaped extension 30 may be dispensed with.

It will be understood that modifications and variations may be effectedwithout departing from the spirit and scope of the novel concepts of thepresent invention.

I claim:

1. A writing instrument comprising: a tubular casing defining first andsecond ends; a centrally apertured point having an outer end projectingbeyond a first end of said casing and having its inner end slidablymounted in said casing for movement from a relatively extended positionto a relatively retracted position with reference to said casing; firstresilient means normally biasing said point to its relatively extendedposition; an elongate cylindrical writing style defining a writing tipand a base end and slidably mounted within said tubular casing betweenan extended position with its writing tip end slidably projected throughsaid centrally apertured point and a retracted position with said endtelescoped within said point; a style actuating member mountedlongitudinally slidably in said casing in engagement with the base endof said style; second resilient means bearing against said actuatingmember biasing said member and said style to its extended position, saidpoint, actuating member, and style being retractable together in saidcasing against the combined forces of said first and second resilientmeans under influence of axial retractive thrust applied to said writingtip and point; a ratchet element mounted in said casing adjacent saidactuating member and having first and second ratchet teeth ofrespectively shorter and longer root depths; a pawl element, one of saidelements being mounted in fixed position in said casing and the other ofsaid elements being carried by said actuating member, with said firstand second teeth limiting the extent of slidable extended movement ofsaid actuating member and style movable therewith following eachsucceeding release of retractive axial thrust, said pawl when engaged inthe root of said first ratchet tooth being operable to retain saidmember and style movable therewith in their retracted positions, saidpawl when engaged in the root of said second ratchet tooth beingoperable to allow said member and style to move to their fully extendedpositions under influence of said second resilient means.

2. A writing instrument according to claim 1 which includes aligningmeans including said first and second ratchet teeth and second resilientmeans for alternatingly aligning said pawl for engagement within therespective root depths of said first and'second ratchet teeth followingeach succeeding release of retractive axial thrust.

3. A writing instrument having a positively operating shifting andlocking mechanism comprising: a tubular casing defining first and secondends; a centrally apertured point member having an outer end projectingbeyond a first end of said casing and having its inner end slidablymounted in said casing for movement from a relatively extended positionto a relatively retracted position with reference to said casing; firstresilient means associated with said point member and normally biasingsaid point member to its relatively extended position; an elongatecylindrical writing style member defining a writing tip and slidablymovable within said tubular casing between an extended position with itswriting tip slidably projected through said centrally apertured pointmember and a retracted position with said tip telescoped within saidpoint member; an actuator in engagement with one of said members forconjoint movement therewith; second resilient means associated with saidstyle member biasing said style member to an extended position, saidpoint member, actuator and style member being retractable together insaid casing against the combined forces of said first and secondresilient means under influence of axial retractive thrust applied tosaid writing tip and point member; a ratchet unit in said casingadajcent said actuator and having first and second ratchet teeth ofrespectively shorter and longer root depths; and a pawl unit; one ofsaid units being held by said actuator and the other of said units beingheld by said casing whereby said ratchet unit and said pawl unit arelongitudinally movable relative to one another upon the application andrelease of retractive axial thrust, said pawl unit when within the rootof said first ratchet tooth being operable to retain said actuator andmember movable therewith in their retracted positions, said pawl unitwhen within the root of said second ratchet tooth being operable toallow said actuator and member movable therewith to move to their fullyextended positions under influence of the resilient means associatedwith said movable member.

4. A writing instrument according to claim 3, wherein said actuator iscarried by said style member.

5. A writing instrument according to claim 4, wherein said pawl unit isheld by said actuator, said ratchet unit is defined by a sleeveencircling said actuator, a third resilient means within said casingengaging said sleeve and urging it into normal engagement with said pawlunit and a stop fixed to said casing and engageable with said ratchetunit, said stop being so positioned to permit the disengagement andrelative longitudinal movement of said pawl unit and said ratchet unitupon the application of said axial retractive thrust.

' 6. A writing instrument according to claim 4, wherein said pawl unitis held by said casing, said ratchet unit is held by said actuator, andwherein said ratchet teeth are in circumferentially spaced relationshipto each other.

7. A writing instrument according to claim 4, which includes aligningmeans for alternatingly aligning said pawl unit for engagement withinthe respective root depths of said first and second ratchet teethfollowing each succeeding release of retractive axial thrust, saidaligning means including said first and second ratchet teeth and saidsecond resilient means.

8. A writing instrument having a positively operating shifting andlocking mechanism comprising: a tubular casing defining first and secondends; a centrally apertured point member carried by said casing havingan outer end projecting beyond a first end of said casing, the

outer end of said point member being movable between a relativelyextended position and a relatively retracted position with reference tosaid casing; an elongate cylindrical writing style member defining awriting tip and mounted within said tubular casing for slidable movementbetween an extended position with its writing tip slidably projectedthrough said centrally apertured point member and a retracted positionwith said tip telescoped within said point member; resilient meanswithin said casing adapted to engage said style member to bias saidstyle member to an extended position; said point member and style memberbeing retractible together in said casing against the force of saidresilient means under influence of axial retractive thrust applied tosaid writing tip and point member; a ratchet unit in said casingdefining first and second ratchet teeth of respectively shorter andlonger root depths; and a pawl unit; one of said units being carried bysaid casing and the other of said units being carried by said stylemember whereby said ratchet unit and said pawl unit are longitudinallymovable relative one another upon the application and release ofretractive axial thrust, said pawl unit when within the root of saidfirst ratchet tooth being operable to retain said style member in itsretracted position, said pawl unit when within the root of said secondratchet tooth being operable to allow said style member to move to itsfully extended position under influence of the resilient meansassociated with said style member.

9. A writing instrument according to claim 8, wherein said first andsecond ratchet teeth define a first set of ratchet teeth, a second setof ratchet teeth defind by said ratchet unit, said second set of teethbeing in spaced and opposed relationship to said first set of ratchetteeth, said pawl unit being alternatingly engageable with said secondand first set of ratchet teeth upon the application and release of saidretractive axial thrust to direct said pawl unit into engagement withinthe root of said first ratchet tooth, said pawl unit being alternatinglyengageable with said second and first set of ratchet teeth upon asucceeding application and release of said retractive axial thrust todirect said pawl unit into engagement within the root of said secondratchet tooth.

10. A writing instrument having a positively operating shifting andlocking mechanism, comprising: a tubular casing defining first andsecond ends; a centrally aperr. tured point member having an outer endprojecting beyond a first end of said casing and having its inner endslidably mounted in said casing for movement from a relatively extendedposition to a relatively retracted position with reference to saidcasing; first resilient means associated with said point member andnormally biasing said point member to its relatively extended position;an elongate cylindrical writing style member defining a writing tip andslidably movable within said tubular casing between an extended positionwith its writing tip slidably projected through said centrally aperturedpoint member and a retracted position with said tip telescoped withinsaid point member; an actuator in engagement with one of said membersand longitudinally movable therewith; second resilient means associatedwith said style member biasing said style member to an extendedposition; said point member, actuator and style member being retractabletogether in said casing against the combined forces of said first andsecond resilient means under influence of axial retractive thrustapplied to said writing tip and point member; a sleeve unit in saidcasing adjacent said actuator and having first and second teeth definingfirst and second abutments, respectively, said abutments beinglongitudinally spaced relative to one another; and a pawl unit; one ofsaid units being carried by said actuator and the other of said unitsbeing carried by said casing whereby said sleeve unit and said pawl unitare longitudinally movable relative to one another upon the applicationand release of retractive axial thrust, said pawl unit when engagingsaid first abutment being operable to retain said actuator and membermovable therewith in their retracted positions, said pawl unit whenengaging said second abutment being operable to allow said actuator andmember movable therewith to move to their fully extended positions underinfluence of the resilient means associated with said movable member.

l l. A writing instrument according to claim 10, wherein said actuatoris carried on said style member, wherein said sleeve unit is carried bysaid actuator and wherein said pawl unit is carried by said casing.

12. A writing instrument according to claim 10, wherein said actuator iscarried by said style member and wherein said sleeve unit is fixed tosaid casing.

References Cited in the file of this patent FOREIGN PATENTS GreatBritain Apr. 5, 1950

